std::max_align_t

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Defined in header <cstddef>
typedef /*implementation-defined*/ max_align_t;		(since C++11)

std::max_align_t is a POD type whose alignment requirement is at least as strict (as large) as that of every scalar type.

Notes

Pointers returned by allocation functions such as std::malloc are suitably aligned for any object, which means they are aligned at least as strict as std::max_align_t.

std::max_align_t is usually synonymous with the largest scalar type, which is long double on most platforms, and its alignment requirement is either 8 or 16.

Example

#include <iostream>
#include <cstddef>
int main()
{
    std::cout << alignof(std::max_align_t) << '\n';
}

Output:

16

See also

alignof operator	queries alignment requirements of a type (since C++11)
alignment_of (C++11)	obtains the type's alignment requirements (class template)
is_scalar (C++11)	checks if a type is scalar type (class template)